Conventional processes for producing tanned leather and tanned leather goods generate considerable waste material. Scraps from cut leather, wet blue shavings from the tanning process, and other leather waste from conventional leather processes is usually bulked and transported to landfills. Disposal of leather waste in this way is environmentally undesirable and can be costly to the leather producer. In addition, chromed tanned leather and chemicals used to produce leather products can be unwanted in landfill operations.
Current approaches to recycling leather waste materials include producing fertilizers by extracting portions of slurried leather. Considerable waste, requiring disposal, can be a byproduct of this extraction process.
Processes for producing a moldable mat from fibrous wood products are well known. One such process is disclosed in U.S. Pat. No. 4,418,031 to Doerer et al. In the Doerer et al. process, cellulose fibers are mixed with synthetic fibers, the synthetic fibers are melted, and then solidified to form a cohesive mat of cellulose and synthetic fibers. This process includes dry blending the fibers together, passing this blend through a former, curing the blend in an oven, and molding the cured blend into a shaped article.
It has been found that utilizing a dry process for making a fibrous mat is environmentally advantageous and relatively time and energy efficient. Typically, if a dry process is used for fibrous mat preparation and processing, then there is no slurry or waste byproduct that has to be discarded.
It should be highly desirable to develop a process for making a reconstituted leather product using limited amounts of water. It would also be highly desirable for this same process to recycle all types of scrap and waste leather and hide materials. Preferably, a process is developed such that the reconstituted leather product is continuously recyclable, that is, the reconstituted product at the end of its useful life is capable of entering the preparation process of the invention as a starting material.
Further, it is desirable to produce a reconstituted leather product having the strength and pliability of real leather. The reconstituted leather product can also have the ability to be cut and sewn into leather-like products. It is also desirable to produce a reconstituted leather product having similar physical properties when compared with natural, unrecycled leather.